In the art various forms of prosthetic heart valve means have been devised, in substantially all of which a leaflet structure is employed and supported in hinging relation to a retainer ring to simulate opening and closing of heart flaps as may occur in an aortic valve; or in a one or two valve flap type mitral valve. All of these prior art structures have limitations of one type or another as has been disclosed in more detail in U.S. Pat. No. 4,114,202 issued to the applicant herein in 1978. Included in these limitations are questions regarding durability, efficiency, undesirable blood changes, and the like. These conditions continue to exist and there is a need for an improved hinging leaflet construction which will meet all of the stringent requirements imposed in cardiovascular surgery.